Some industrial vehicles, such as tractors and towed implements used on farms and operated down the rows of cultivated crops require some adjustability in the lateral spacing of the wheels from each other, both front wheels and rear wheels. For example, the ideal lateral spacing of some row crops is different from the spacing of other row crops, since some crops can be planted closer together to maximize the yield in a given area of land. Therefore, it is desirable that the vehicles operated along the rows of cultivated crops have the ability to increase or decrease the lateral distances between the wheels of the vehicles.
One of the common ways of changing the lateral spacing of wheels of a vehicle is to construct the discs of the wheels in a dish-shape, having opposed concave and convex surfaces, so that the hub portion of the wheel disc is axially offset to one side of the center line of the wheel. Therefore, a pair of wheels for the vehicle can be mounted with their convex sides attached to the wheel hub to space the tires further apart, or the wheels can be reversed to mount their concave sides to the wheel hub, placing the tires closer together.
While the above-described wheel spacing adjustability is common in the art, other means are required for providing more versatility in wheel spacing of vehicles. Various spacers have been developed over the years for placement between the wheel rim and the tractor hub to refine wheel displacement for the vehicle, but the prior art adjustment elements for wheels is, generally, cumbersome and in some cases not as safe as a standard wheel mount. Also, while various adjustable rim assemblies have been provided for mounting a wheel rim to the outwardly facing surface of the hub of a wheel assembly, it would also be desirable to be able to mount the wheel rim to the inner facing surface of the hub so as to further displace the tire inwardly with respect to the vehicle. While this is physically possible, the prior art does not provide an adjustable wheel rim structure that can be expediently and safely mounted to the interior surface of a wheel hub without sacrificing strength of the connection.
Thus, it is to these ends that this invention is directed.